Abstract:

The cold flow property of biodiesel can be effectively improved by pour point depressants (PPD). The terpolymer (AHM) was prepared by solution polymerization of hexadecyl methacrylate, hydroxyethyl methacrylate and maleic anhydride. The effect of AHM on pour point reduction of biodiesel was also investigated. The hexadecyl methacrylate and AHM were characterized by infrared spectroscopy. The optimal reaction conditions of AHM were determined by single factor experiment: n(hexadecyl methacrylate)/n(hydroxyethyl methacrylate)/n(maleic anhydride)=2∶1∶2, the initiator mass fraction is 3.0%, the solvent mass fraction is 65%, the reaction time is 3 h, and the reaction temperature is 85 ℃. When the mass fraction of AHM is 0.7%, the freezing point of biodiesel decreased by 12 ℃. The morphology of wax crystals precipitated from biodiesel at low temperature after adding pour point depressant was observed by polarizing microscope, and the morphology was more uniform and dense.

Key words: Biodiesel, Hydroxyethyl methacrylate, Pour point depressant

摘要：

降凝剂可以有效地改善生物柴油的低温流动性，采用溶液聚合法制备了甲基丙烯酸十六酯、甲基丙烯酸羟乙酯和马来酸酐的共聚物（AHM），并考察了AHM对生物柴油降凝效果的影响。采用红外光谱（IR）对甲基丙烯酸十六酯和AHM进行了表征。通过单因素实验的方法确定了AHM的最佳反应条件：n(甲基丙烯酸十六酯)/n(甲基丙烯酸羟乙酯)/n(马来酸酐)=2∶1∶2，引发剂质量分数为3.0%，溶剂质量分数为65%，反应时间为3 h，反应温度为85 ℃。当AHM质量分数为0.7%时，生物柴油的凝点降低12 ℃。采用偏光显微镜观察了加入降凝剂后生物柴油在低温下析出的蜡晶形态，其形态更加均匀致密。

关键词: 生物柴油, 甲基丙烯酸羟乙酯, 降凝剂